For the suctioning of bodily fluids or secretions from body cavities or wounds, stationary aspiration systems have generally been used in the field of medicine, especially for thoracic drainage. These aspiration systems basically consist of a suction source, especially a vacuum pump, a fluid or secretion collection reservoir, a surge tank arranged in between them, as well as connection lines, namely, a drainage line going from a patient to the secretion reservoir, a connection line going from the secretion reservoir to the surge tank, and a vacuum line connecting the surge tank to the suction source.
While these aspiration systems have proven to work well in practice, it is essential to the healing process, especially after surgery in the chest region, for the patient to be able to move and leave his or her bed as soon as possible.
Therefore, it has already been proposed to secure all the aforesaid components of the drainage system on a movable frame, so that the patient can gain a certain mobility, at least within the hospital.
Moreover, portable aspiration units are known, which substantially improve the mobility range of the patient. These portable aspiration units are used for the most part in wound drainage.
U.S. Pat. No. 6,352,525, however, discloses a portable pump unit which is said to be suitable for thoracic drainage. It can be fastened to the patient's body and thus allows him to move freely and relatively unimpeded. A vacuum pump, an energy source, a vacuum chamber and a secretion collecting reservoir are integrated in this drainage pump unit. The vacuum chamber is arranged in a first part, the secretion collecting reservoir in a second part and the vacuum pump in a third part. The first and third part in the working position are arranged above the second part and detachably joined to each other, as well as to the second part. Drainage connectors and vacuum connectors join the corresponding parts to each other. This device is relatively complex in construction and, what is more, it is not very easy to clean.
WO 99/10024 describes a portable pump unit for thoracic drainage, which is connected via an external line to an equally portable kidney-shaped secretion collecting reservoir. This device has the drawback that two separate units have to be carried, and what is more they are joined to each other via a hose.
In addition, EP-A-1184043 discloses a small-size aspiration pump, especially for wound drainage, which has a catchment reservoir for aspirated material and a cover, with all pump components essential to its working being integrated in the cover of the reservoir.